11 



ORDER 11. 



SAURIA*.— THE SAURIANS. 



The Saurian Reptiles have a heart like that of the Tortoises, composed 

 of two auricles and one ventricle, which is sometimes divided by imperfect 

 partitions. 



Their ribs are moveable, are partially connected with the sternum, and 

 can be raised or depressed in respiration. 



Their lung extends more or less towards the posterior extremity of the 

 body; it frequently penetrates very far into the lower part of the abdo- 

 men, the transverse muscles of which pass under the ribs, and even 

 towards the neck, to clasp it. Those in which this organ is very large, 

 possess the singular faculty of changing the colours of their skin accord- 

 ing to the excitement produced in them by their wants or passions. 



Their eggs are enveloped by a covering more or less hard, and the 

 young emerge from them with the form which they permanently keep. 



Their mouth is always armed with teeth, and their toes, with very few 

 exceptions, are furnished with nails; their skin is covered with scales, 

 more or less compact, or at least with scaly granules. They couple, 

 either with two male organs or with one, according to their genera. 

 They all have a tail more or less long, and generally very thick at its 

 base : most of them have four legs, a few only having but two. 



Linnaeus included them all in two genera, the Dragons and the 

 Lizards: but it has been found necessary to divide the latter into seve- 

 ral, which so far differ in the number of feet, &c., the shape of the 

 tongue, tail and scales, that we are even compelled to distribute them into 

 several families. 



FAMILY I. 



CROCODILIDA.— THE CROCODILES, 



Which contains only a single genus, 



Ckocodilus, Br. 



They have a considerable stature; their tail is flattened on the sides, 

 five toes before and four behind, of which only the three internal ones on 



From the Gr. sauros, (lizard), animals analogous to Lizards. 



